Fluorinated organic compounds and polymers thereof



3,020,267 FLUGRINATED ORGANIC COMPOUND AND POLYMERS 'lll-EREOF John T.Barr, Needham, Mass, assignor to Pennsalt Qhemicals Corporation, acorporation of Pennsylvania No Drawing. Filed Nov. 17, 1955, Ser. No.547,538 13 Claims. (Cl. 260-92.1)

This invention relates to new chlorine-substituted fluorodiolefins. Moreparticularly it relates to chlorinesubstituted fluorobutadicnes, tomethods for their preparation and to the intermediate compounds involvedin said methods of preparation. It further relates to polymers andcopolymers of said chlorine-substituted fluorodienes and to processesfor their preparation.

The object of this invention is the preparation of novel polymerizabledienes with predetermined properties from which polymeric materials ofsuperior chemical and physical properties can be prepared. At thepresent time there are a large number of fluorine-containing dieneswhich have been prepared and polymerized with the goal of obtaining apolymeric rubber-like product of high commercial value and utility atlow cost. However, the majority of such dienes have had various failingswhen polymerized. Polymerization has been very diflicult in most cases;oxidation stability of the polymers at temperatures substantially over100 C. has been poor; and copolymerization with another monomer isusually required to get reasonable yields and acceptable properties.

It has now been found that certain highly fluorinated dienes in whichthe fluorine is present in alternating CF and =CF-CH= groupings, such asthose disclosed in my co-pending application Ser. No. 421,677, filedApril 7, 1954, can be modified by the substitution of chlorine for aportion of the hydrogen and fluorine in the molecule to form a dienewith a molecular structure which has greatly improved stability andresistance to oxidation. Furthermore, monomeric dienes with this newmodified structure can be polymerized readily into rubber-like polymerswith correspondingly enhanced properties and at lower cost.

Among the advantages resulting from such monomers and polymers thefollowing are outstanding: (I) increased chemical and physical stabilityand oxidation resistance of the monomers and polymers, (2) decreasedtendency for spontaneous polymerization among some of the unsymmetricalpartially-fluorinated dienes, resulting in simplified storage andhandling of the monomers, and (3) reduced crystallinity of therubber-like products which can be formed, resulting in enhanced physicalproperties and a wider usable temperature range of the polymers.

These advantages are obtained only through a careful selection of thehalogen content of the diene. Not all dienes of the same empiricalformula possess the desired feature embodied in my invention.

Two conditions must be met in order to obtain the compounds of myinvention and a third condition should be met in order to obtain mypreferred compounds, which offer maximum benefit from the halogencontent of the diene. First, in order to obtain maximum oxidationresistance of the polymer, the residual double bond in the polymer mustbe flanked by two negative substituent groups, for example, substitutedalkyl or halogen atoms, preferably at least one of which is fluorine.Thus, the diene must have the structure C=CXCY'=C in which X ischlorine, fluorine, or substituted alkyl with 1 to 12 carbon atoms, andY is chlorine or fluorine. Secondly, the diene must have anunsymmetrical distribution of the halogens; and since it has been foundthat at least two fluorine atoms should be present to impart the desiredtendency toward polymerization, stability and oil resistance of thepolymer, this then requires that the structure of the diene beCFX=CXCY=CHX, where X andY' are as defined above, and X is hydrogen,chlorine or fluorine, and at least one of X, X or Y is a fluorine. Thethird condition which must be met for my preferred compounds is that forextreme temperature service there must be little tendency for theelements H and X to be lost from adjacent carbon atoms. To meet thismost stringent requirement there should be no carbon having both ahalogen and a hydrogen. This then dictates that the structure of thediene be CF =CXCY=CH which is the preferred structure of this invention,X and Y being as given above; however, where the temperature service isnot as severe, say below 350 R, but where maximum resistance to oils andsolvents is desired, the more highly halogenated form CFX=CX-CY=CHX', inwhich X, X and Y are as given above, is of advantage and should be used.Also, in cases where more rubbery qualities are'required, more of thehalogen may be replaced by alkyl or substituted alkyl groups.

The diolefins which have been found useful 'in this invention may berepresented by the structure where Xis chlorine, fluorine, orsubstituted alkyl with 1 to 12 carbon atoms; X is hydrogen, chlorine orfluorine; and Y is chlorine orfluorine.

The preferred structure is CF =CXCY=CH in which X and Y are as describedabove.

A number of synthetic routes to the above diolefins will be apparent tothose skilled in the art. A very convenient route is from the butenesdisclosed in my co-pending application Serial No. 421,667, dated April7, 1954, which discloses butenes of the structure The butenes which aremost useful in the synthesis of the diolefins of this invention arethose in which, in the above structure, X is chlorine,- fluorine, orsubstituted alkyl with 1 to 12 carbon atoms; Y is chlorine or bromine;

and X is hydrogen, chlorine or fluorine, with the distribution of thehalogens limited by the structure of the diene desired; The hydrogen ofthe third carbon atom may be replaced by a halogen in some cases Wheredirect dehalogenation is used as the route to the diene desired.

Some specific examples of starting butenes and the chlorine-substitutedfluorodiolefins derived from them by the process of this invention arethe following:

In forming the dienes of this invention from the stipulated butenes itis necessary to pass through an intermediary stage comprising theformation of a new series of butanes from which the butadienes areultimately formed by dehydrohalogenation and/or dehalogenation. This newseries of butanes has the structure CFXY CXY-CHYCHX'Y in which X ischlorine, fluorine, or substituted alkyl with 1 to 12 carbon atoms; X ishydrogen, chlorine or fluorine; Y is bromine or chlorine; and Y ischlorine or fluorine. It will be apparent, as my invention is furtherdescribed, that many butanes of a series with the above structure can bemade from each of the stipulated butenes. It is not deemed necessary tomake a complete listing of these possible butanes; however, for example,the following butanes of this invention can be made and in turn used tomake many desired chlorine-substituted fluorinated butadienes of thisinvention.

Butane:

1-bromo-2,3 ,4-trich1oro- 1 1 ,Z-trifluorobutane Butadiene:

3-chloro-1,1,Z-trifiuorobutadiene-l,3 Butane:

1-bromo-2,3,4,4-tetrachloro-1,1,2-trifiuorobutane Butadiene:

3,4-dichloro-1,1,2-trifiuorobutadiene-1 ,3 Butane:

1-bromo-2,3,3,4-tetrachl0ro-1,1,2-trifluorobutane Butadienesi3,4dichloro-1,1,2-trifluorobutadiene-1,3 by dehydrohalogenation followedby dehalogenation. 3-chloro-1,1,2-trifluorobutadiene-1,3 directly bydehalogenation. Butane:

1-bromo-2,2,3,4-tetrachloro-1,l-difluorobutane Butadiene:

2,3-dichloro-l,1-difiuorobutadiene-l,3 Butane:

1-bromo-2,3,4-trichloro-1,1,2,4-tetrafiuorobutane Butadiene:

3-chloro-1,1,2,4-tetrafluorobutadiene-1,3

Many other examples are possible.

In a preferred embodiment of my invention conversion of the stipulatedbutenes to the desired butanes and then to the desired dienes is carriedout by the alternate chlorination of the butene to a butane followed bydehydrochlorination of the butane until a butene is obtained which will,upon dehalogenation, produce the desired diene. The alternation may beomitted if the desired diene has halogen on both the third and fourthcarbons, and the steps in the synthesis consist of (a) chlorination ofthe butene to a desired butane followed by (12) direct dehalogenation tothe desired diene.

Chlorination of the 'butene and butane may be effected by any one of themeans known to the art; however, for simplicity, direct use of chlorineis preferred for the process of this invention.

Dehydrohalogenation of the butane and butene may be done by any of themeans known to the art, i.e., treatment wtih alcoholic potassium orsodium hydroxide solution, treatment with aqueous calcium hydroxidesuspension, thermal cracking, or treatment with organic bases or ferricchloride. Dehydrohalogenation with alcoholic potassium hydroxidesolution is a preferred method in my invention.

Similarly, any method known to the art may be used for dehaloigenationof the butane, including heating with metallic iron or zinc, or use ofsodium amalgam. The preferred method in this invention is the use ofzinc dust in the presence of refluxing alcohol.

In further practicing my invention the chlorine substitutedfiuorodiolefins prepared according to the instructions of this inventionare subjected to polymerization conditions. The chlorine-substitutedfiuorobutadienes described in an earlier section of this invention, andof 4 the structure CFX=CXCY=CHX', in which X is chlorine, fluorine orsubstituted alkyl with 1 to 12 carbon atoms; X is hydrogen, chlorine orfluorine; and Y is chlorine or fluorine; and of which CF =CXCY=CH is apreferred form, may be homopolymerized or copolymerized readily toprepare rubber-like polymers.

Emulsion polymerization conditions are preferred but other knownpolymerization techniques such as mass or solution polymerization mayalso be used. In preferred embodiments of my invention Water is mixedwith the monomer or comonomers, an emulsifying agent and a catalyst orpolymerization initiator are added and the mixture is agitated. Thedegree and rate of polymerization may advantageously be controlled byvarying the amount of catalyst used and the temperature.

In preparing copolymers according to my invention the proportions of thechlorine-substituted fiuorobutadiene and the comonomer used may bevaried considerably within the scope of the invention, depending on theproperties desired in the copolymer. For example, copolymers containingas little as 0.5 or as much as 95 mol percent of thechlorine-substituted fluorobutadiene may beused advantageously inpracticing my invention. The preferred proportions are 20 to mol percentof the chlorine-substituted fluorobutadiene and 80 to 20 mol percent ofa comonomer.

The homopolymerization and copolymerization reactions according to myinvention may be carried out at temperatures of from below 0 C. to thecritical temperature of the monomer or of the mixture of monomers. Thepreferred reaction temperature is from 5 to 60 C.

The amount of water used in carrying out an emulsion polymerization orcopolymerization is not critical, but for practical purposes it ispreferred to use an amount of from 1 to 4 times the weight of themonomer or of the combined monomers. A sodium lauryl sulfate compoundknown under the trade name of Dupanol WA or Dupanol ME has been used asemulsifying agent in the polymerization and copolyrnerization reactionsof this invention, although other conventional emulsifying agents mayalso be used. The amount of emulsifying agent may be varied from about0.1% to about 15% of the weight of the monomer, or of the combinedmonomers, although the preferred amount is from 1% to 10%.

A number of materials are known to the art as emulsion polymerizationcatalysts or initiators and almost any of these may be used. A fewexamples of such materials are oxygen, ozone, hydrogen peroxide, benzoylperoxide, cumene hydroperoxide and other organic peroxides, organicozonides, peroarbonates perhorates, perchlorates, and persulfates. Thepreferred catalysts for emulsion polymerizations in the practice of myinvention are the persulfates of ammonium, sodium and potassium. Thespeed of the emulsion polymerization reaction is partially dependent onthe amount of catalyst used, and in operating the process of myinvention with potassium persulfate as catalyst, the amount may bevaried from about 0.05% to as much as 4% of the weight of the monomer orcombined monomers although the preferred amount is from 0.5% to 2.5%.

A number of catalysts are known to the art as mass polymerizationcatalysts or initiators and almost any of these may be used. A fewexamples of such materials are organic peroxides, such as acetyl,benzoyl, tertiary butyl or cumene hydroperoxide and motazodi-isobutyronitrile. Other useful initiators are ultraviolet light,sunlight, ozone and certain radioactive materials. The preferredcatalysts for mass polymerizations in the practice of my invention areacetyl and benzoyl peroxides and wet azodi-isobytryronitrile. The speedof the mass polymerization is partially dependent on the amount ofcatalyst used, and in operating the process of my invention with thepreferred catalysts the amount may be varied from about 0.001% to asmuch as 5% of the weight of monomer of combined monomers, although thepreferred amount is from 0.1% to 1%.

It is clear to those skilled in the art that since the temperature andamount of catalyst affect the rate of reaction, they also affect thereaction time. With this understood, it becomes apparent that thereaction time can be varied over a wide range, depending upon theparticular conditions used and the degree of polymerization desired. Ingeneral a reaction time of from to 60 hours has been found to besuitable and practical, although good results may also be obtained usingless than 5 hours or longer than 60 hours.

Auxiliary polymerization agents known to the art, although not essentialto the operation of my invention, may be used to advantage. For example,a small amount of sodium bisulfite added initially helps to activate thepoly merization catalyst and thus promotes the start of the reaction. Asmall amount of buffer, such as borax, is also helpful in preventingchanges in pH caused by slight hydrolysis of the reactants. A smallamount of a mercaptan, such as tertiary dodecyl mercaptan, is effectivein regulating the polymer molecular Weight and preventing the formationof excessively high molecular weight products from certain monomerpairs.

Although one of the objects of my invention is to make available newcopolymers of chlorine-substituted fluorobutadienes with other monomers,it is to be understood also that in some cases the products of myinvention may contain homopolymers of the monomer used in excess inaddition to the said copolymers. This is particularly true when thecopolymerization is carried out using only a very small proportion ofone of the monomers. One special value of the coplymerization processunder those conditions is that it provides an added means of Widelyvarying the range of chemical and physical properties which can beobtained.

In general the homopolymers and copolymers of chlorine-substitutedfluorobutadienes which have the most Valuable properties arethermoplastic solids, although valuable products ranging from viscousliquids to hard solids at ordinary temperatures may also be prepared,depending on the application desired, by varying the degree ofpolymerization of the monomer or monomers and by selection of a suitablecomonomer to obtain a desired copolymer with predetermined properties.Copolymeric products prepared according to my invention may contain from0.5 to 95 mol percent combined chlorine-substituted fluoro butadiene andfrom 99.5 to 5 mol percent of one or more combined cornonomers, butpreferred products contain from 20 to 80 mol percent combinedchlorine-substituted fluorobutadienes with themselves or with othercomonomers.

The preferred homopolymers are those prepared from dienes with thestructure CF =CXCY'=CH in which X is chlorine, fluorine, or substitutedalkyl with 1 to 12 carbon atoms and Y is chlorine or fluorine. Aspecific example of such a preferred homopolymer is the homopolymer of3-chloro-1,l,2-trifluorobutadiene-l,3,

a monomer possessing the above stipulated structure and in whichstructure X is fluorine and Y is chlorine. Other specific examples arehomopolymers of the following: 4- chlorol,1,-2-trifluorobutadiene-1,3;3,4-dichloro-1,1,2-trifiuorobutadiene-l,3;2,3-dichloro-1,l-difiuorobutadiene-l, 3; 2,3,4-trichloro-1, 1-difiuorobutadiene-1, 3; 3 -chloro-l 1 ,2, 4-tetrafluorobutadiene-1,3;1,3'dichloro-1,2-difluorobutadiene-1,3;1,3,4-trichl0ro-l,2-difluorobutadiene-1,3;2-trifiuorornethyl-1,1-difluorobutadiene-l,3;3-chloro-2-pentafiuoroethyl-1,1-difluorobutadiene-1,3; and2-chloro-3-trifluoromethyl-l,1difiuorobutadiene-l,3.

Copolymers made according to my invention include polymeric products ofchlorine-substituted fluorobutadienes with other polymerizable organicmonomers having at least one ethylenic linkage and the structure inwhich X and X are selected from the group consisting of hydrogen andfluorine; Y is selected from the group consisting of hydrogen, fluorine,and lower alkyl with l to 12 carbon atoms; and Y is selected from thegroup consisting of hydrogen, chlorine, fluorine, alkyl with 1 to 12carbon atoms, substituted alkyl with l to 12 carbon atoms, carbalkoxy,aryl or substituted aryl. Examples of some of these are ethylene, vinylchloride, acrylonitrile, styrene, 2,2,2-trifiuoroethyl vinyl ether,2,2,2-trifluoroethyl acrylate, perfluorobutadiene-1,3, methyl acrylate,methyl methacrylate, butadiene, etc. 7

Polymeric products of my invention which have the most valuableproperties are rubbery solids, although valuable products ranging fromviscous liquids to hard solids at ordinary temperatures may also beprepared, depending upon the application desired, by varying the degreeof polymerization, and in the case of copolymers, use of a selectedcomonomer which will result in a product with the predeterminedproperties desired.

Rubbers prepared by curing the polymeric products of this invention havesuperior mechanical properties as compared to other highly fluorinatedrubbers or rubbery polymers. They also have outstanding resistance tosolvents, oils, oxygen, sunlight, heat, aging, acids, alkalies,

and other chemicals, and are particularly useful Where resistance tothese is necessary, as for example in the chemical process and alliedindustries. Examples of especially valuable applications includegaskets, packings, flexible piping, hose, linings, coatings, chemicallyresistant gloves and boots, wire coating, etc.

The invention and its practice are further illustrated by the followingexamples, in which the parts are by weight.

EXAMPLE I Preparation of 3-chl0ro-1,1,Z-trifluorobutadiene-I,3

Chlorine was passed into a solution of 1-brorno-2-chloro-l,l,2-trifluorobutene-3 in an equal part of carbon tetrachlorideuntil the weight increase of the solution indicated that the theoreticalamount of chlorine required just to saturate the double bond had beenabsorbed. Distillation gave a yield of 1-bromo-2,3,4-trichloro-1,1,2-trifluorobutane (B.P. -183 C., n 1.4540), and an 8% yield of amixture of l-bromo-2,3,4,4-tetrachloro-1,l,Z-trifiuorobutane andl-bromo-2,3,3,4-tetrachloro-l,1,2-triiiuorobutane, but predominantly theformer (B.P. 9699 C. at 12 mm., 11 1.4718).

Dehydrochlorination of the l-bromo-2,3,4-trichloro-1,1,2-trifluorobutane by KOH in alcohol at 0 to 10 C. gave an 83% yieldof 1-bromo-2,3-dichloro-1,1,2-trifluorobutene-3 (B.P. 132-434 C., 111.4330).

The 1-bromo-2,3-dichloro-1,1,2-trifiuorobutene-3 was then dehalogenatedby dropping it into a refluxing suspension of zinc dust in alcoholcontaining a little t-butyl catechol. The mixture was refluxed 1/3hours, then cooled and filtered. Addition of 2 volumes of water and alittle HCl to the filtrate resulted in the formation of a lower layerwhich was separated, Washed, dried and distilled. The product was3-chloro-1,1,2-trifluorobutadiene-1,3 (B.P. 54 (1., 11; 1.3835). Aconversion of 43.5% was obtained.

The S-chloro-l,1,2-trifluorobutadiene-1,3 was homopolymerized in 90%conversion to form a soft elastomer which was vulcanized into a strongrubbery material. It was copolymerized in 3:1 ratio with styrene to 73%conversion. It was also copolymerized with trifluoroethyl vinyl ether in1:1.36 ratio to 63% conversion.

The high boiling mixture of1-bromo-2,3,4,4-tetrachlorol,l,2-trifluorobutane and1-bromo-2,3,3,4-tetrachloro- 1,1,2-trifluorobutane was dehalogenateddirectly and the isomer 4-chloro-1,1,2-trifluorobutadiene was isolated.This diene was also polymerized to a soft elastomer which vulcanized toa strong rubbery material.

EXAMPLE 11 Preparation of 4-chl0r0-1,1,Z-trifluorobutadiene-I .3

Excess chlorine was passed into a 1:1 solution of 1bromo-Z-chloro-1,1,2-tritluorobutene-3 in carbon tetrachloride at reiiuxin the presence of ultraviolet light irradiation beyond the weightrequired to saturate the double bond. Distillation gave a 50% yield ofthe adduct, l-bromo-2,3,4-trichloro-1,1,2-trifiuorobutane, and a 35%yield of 1-bromo-2,3,4,4-tetrachloro-1,1,2-trifiuorobutane (B.P. 103 to107 C. at 17 mm, n 1.4700).

250 g. of the 1-bromo-2,3,4,4-tetrachloro-1,1,2-triiluorobutane wereadded dropwise to 60 g. of zinc dust in 500 ml. of refluxing alcohol andrefluxed for 2 hours. Dilution of the mixture with water gave a lowerlayer which was washed, dried and distilled to give 65 g. of4-chloro-1,l,2-trifluorobutadiene-l,3 (B.P. 70 to 73 C.).

EXAMPLE III Preparation of 3,4-diclzlr0-1,LZ-trifluorobutadiene Chlorinewas passed into a 1:1 solution of l-bromo-2,3-dichloro-1,1,2-trifluorobutene-3 in carbon tetrachloride at 50 to 60C. until the double bond was saturated. An 85% yield of1-bromo-2,3,3,4-tetrach1oro-1,1,2-trifluorobutane (B.P. 109 C. at 25mun, 719 1.4755) was recovered on distillation.

Dehydrochlorination of this butane at to C. by KOH in alcohol gave a 75%yield of 1-bromo-2,3,4-trichloro-l,1,2-trifiuorobutene-3, (B.P. 85-86 C.at 85 mm., 11 1.4580).

Dehalogenation of this butene by zinc dust in boiling ethanol gave aconversion to 3,4'dichloro-1,1,2-tri fluorobutadiene-1,3 (B.P. 8590 C.,n;, 1.4116).

This same diene was obtained by dehydrochlorination of the mixture of1-bromo-2,3,4,4-tetrachloro-1,1,2-trifluorobutane and1-bromo-2,3,3,4-tetrachloro-1,1,2-trifiuorobutane of Example 1, followedby dehalogenation of the resulting butene.

The 3,4-dichloro-l,1,Z-trifluorobutadiene-1,3 was homopolymerized with61% conversion to a soft elastomer and vulcanized to a stiff, strongrubbery material.

Copolymerization of the 3,4-dichloro-1,1,2-trifluorobutadiene-l,3 withtrifiuoroethyl vinyl ether resulted in a 27% conversion to a soft, weakproduct.

EXAMPLE IV In order to compare the added storage stability of 3-chloro-l,1,2-trifluorobutadiene-1,3 over similar dienes not possessingthe 3-halo structure, ampoules were charged with it and some similardienes under vacuum conditions and sealed. The following samples wereprepared and treated as indicated:

Ampoule Monomer Parts Added Material 1 1,1,2-trifluor0butadiam-1,3. 10None.

2 3-ohloro-1,1,2-trifluorobutadl- 10 D0.

ens-1,3.

3 .do 10 Do.

4 do 10 04,11 azodi-isohutyronitrile, 0.01 pa 5 do 10 t-butyl catechol,

0.1 part.

6 1,1,2-tr1fiuor0butadiene-1,3- 10 t-butyl eatechol,

0.1 part.

in addition to the 3-cl1loro-1,1,Z-trifiuorobutadiene-l,3, contained aplug of rubbery solid product of high tensile strength. Ampoule 2 wasmaintained at 65 C. for an additional period of time. In the firstadditional day at this temperature a noticeable increase in viscosityoccurred. After a week at 65 C. the material would not flow. Ampoules 3and 5, containing 3-chlorc-l,l,2-trifluorobutadiene-L3 were kept at 25i3C. for three months at which time the contents of am-poule 3 were veryviscous, but the contents of ampoule 5 showed no noticeable change fromits appearance when charged.

EXAMPLE V A pressure reactor was charged with 100 parts 3-chloro-l,1,2-trifiuorobutadiene-1,3, 180 parts water, 5 parts DupanolWA, 4 parts borax, 4 parts potassium persulfate, 4 parts sodiumbisulfite, and 1 part tertiary dodecyl mercaptan. The void space waspurged with nitrogen, and the reactor was sealed. The reactor was heatedat 50 C. and rotated at 29 r.p.m. for 24 hours. parts of soft whiterubbery products were obtained.

parts of product were compounded and milled with 1 part paraifin, 40parts Philblack 0 (carbon black), 0.5 part Z-mercaptoimidiazol. and 1part benzothiazyl disulfide. The product was cured at 310 F. and 500p.s.i.g. for 30 minutes to give a strong rubbery sheet possessing goodphysical properties.

EXAMPLE VI A pressure reactor was charged with 100 parts 3-chlo-ro-1,1,2-trifiuorobutadiene-1,3, 180 parts water, 1 part potassiumpersulfate, 0.5 part borax, 0.5 part sodium bisulfite, and 3 partsDupanol ME. The void space was purged with nitrogen, the unit sealed andheated at 50 C. for 24 hours while being rotated at 29 rpm. In duplicateInns 98.7 and 91.2 parts of soft white rubbery product were obtained.

EXAMPLE VII A pressure reactor was charged with 100 parts S-chloro-1,1,2-trifiuorobutadiene-l,3, parts water, 0.75 part potassiumpersulfate and 2.5 parts Aerosol OT, the dioctyl ester of sodiumsulfosuccinic acid. The charge was treated as in Example VI. 92.5 partsof soft White rubbery polymer were obtained.

EXAMPLE VH1 A pressure reactor was charged with 100 parts 3,4-dichloro-l,1,2-trifiuorobutadiene-1,3, parts water, 5 parts Dupanol WA,4 parts borax, 4 parts potassium persnlf-ate, 4 parts sodium bisulfite,and 1 part tertiary dodecyl mercaptan. The charge was treated as underExample VI. 91 parts of a tough white rubbery product were obtained.This product was vulcanizable by conventional curing procedures to avery strong rubbery stock.

EXAMPLE IX 100 parts3-cholro-2-(2,2,2-trifluoroethyl)-l,1-difluorobutadiene-l,3 werepolymerized for 40 hours using the recipe and procedures of Example VI.53 parts of soft rubbery product were obtained.

EXAMPLE X 100 parts3-chloro-2-pentafiuoroethyl-l,l-difiuorobutadiene-l,3 were polymerizedfor 21 hours using the recipe and procedures of Example VI. 48 parts ofa weak rubbery product were obtained.

EXAMPLE XI 100 parts 2-chloro-3-methyl-1,l-difluorobutadienedfi werepolymerized for 8 hours using the recipe and procedures of Example VI.73 parts of strong rubbery product were obtained.

9 EXAMPLE XII 100 parts 2,3,4-trichloro-1,l-difluorobutadiene-l,3 werepolymerized for 40 hours using the recipe and procedures of Example VI.36 parts of tough hard product were obtained.

EXAMPLE XIH 55 parts of S-choloro-1,1,2-trifiuorobutadiene-1,3 weremixed with 45 parts 2,2,2-trifiuoroethyl vinyl ether and polymerized for20 hours using the recipe and procedures of Example VI. 55 parts of veryrubbery product were obtained.

EXAMPLE XIV 87.5 parts 3-chloro-1,1,2-trifluorobutadiene-1,3 were mixedwith 12.5 parts acrylonitrile and polymerized for 20 hours using therecipe and procedures of Example VI. 16 parts of a sticky plasticproduct were obtained.

EXAMPLE XV 75 parts 3-chloro-1,1,2-trifiuorobutadiene-1,3 were mixedwith 25 parts styrene and polymerized for 20 hours using the recipe andprocedures of Example VI. 90 parts of stiff rubbery product wereobtained.

EXAMPLE XVII 52.5 parts 3-chloro-1,1,2-triflu0robutadiene-1,3 were mixedwith 47.5 parts perfiuorobutadiene-1,3 and polymerized for 25 hoursusing the recipe and procedures of Example VI. 45 parts of soft rubberyproduct were Obtained.

EXAMPLE XVIII 75 parts 3,4-dichloro-1,1,2-trifluorobutadiene-1,3 weremixed with 25 parts styrene and polymerized for 18 hours using therecipe and procedures of Example VI. 70 parts of resinous product wereobtained.

EXAMPLE )GX 75 parts 3,4-dichloro-1,1,2-trifluorobutadiene-1,3 weremixed with 25 parts acrylonitrile and polymerized for 18 hours using therecipe and procedures of Example VI. 25 parts of resinous product wereobtained.

It will be obvious to those skilled in the art that many modificationsmay be made within the scope of the present invention without departingfrom the spirit thereof and the invention includes all suchmodifications.

From the detailed specific examples and the general discussionpresented, it will be evident that this invention provides a series ofnovel polymerizable chemical compounds and intermediate compounds,including methods for their preparation, and further provides a seriesof novel homoand copolymeric products and processes for theirpreparation. The compounds are relatively simple to prepare from easilyavailable starting materials andmay readily be made in availableequipment commonly used in the art. In addition to the important roleplayed by the intermediate compounds in the preparation of the ultimateproducts, the intermediate compounds themselves possess valuableproperties which make them usetul as solvents and as intermediarychemicals in the preparation of other chemical compounds.

From the foregoing disclosures it is clear that incorporation ofchlorine into the fluorine-containing monomer, according to thisinvention, results in new monomers and polymers and intermediateproducts possessing important new characteristics which can be used toadvantage in a large number of commercial products.

I claim:

1. A polymer selected from the group consisting of 75 polymeric CF=CF-CCl=CH CF =CF-CH=CHC1 and CF =CFCCl=CHCl.

2. A homopolymer of CF =CF-CCl=CH 3. A homopolymer of CF CF-CH=CHCL 5 4.A homopolymer of CF =CFCCl=CHCl.

5. A compound selected from the group consisting of CF =CF-CC1=CHC1 6. Acompound having the formula CF =CFCCl=CH 7. A compound having theformula CF =CF--CH=CHC1 8. A compound having the formula CF =CF-CCl=CHCl9. A process for preparing a homopolymer of a monomer selected from thegroup consisting of which comprises polymerizing said monomer in thepresence of a free radical producing catalyst at a temperature in therange from below about 0 to about 100 C. for 5 to 60 hours.

10. A process for preparing a homopolymer of a monomer selected from thegroup consisting of which comprises mixing the monomer with 1 to 4 partsof water, 0.1% to by weight of monomer of cmulsifying agent, 0.001% to5% by weight of monomer of a free radical producing catalyst andagitating and polymerizing the mixture at a temperature in the range offrom about 5 C. to about 60 C. for from 5 to 60 hours.

11. The process that comprises chlorinating l-bromo-2,3-dichloro-1,1,2-trifluorobutene-3, recovering l-bromo-2,3,3,4-tetrachloro-1,1,2-trifluorobutane as product,dehydrochlorinating said product to form1-bromo-2,3,4-trichloro-l,1,2-trifluorobutene-3 anddebrornodechlorinating said latter butene to remove the bromine atomfrom the first carbon atom and the chlorine atom from the second carbonatom to form 3,4-dichloro-1,1,2-trifluorobutadiene-l,3.

12. The process that comprises chlorinating l-bromo- 2-chloro 1,1,2trifluorobutene 3, recovering 1 bromo-2,3,4-trichloro-1,1,2-trifluorobutane as product, dehydrochlorinatingsaid product to form 1-bromo-2,3-dichloro 1,1,2-trifluorobutene-3 anddebromo-dechlorinating said latter butene to remove the bromine atomfrom the first carbon atom and the chlorine atom from the second carbonatom to form 3-chloro-1,1,2-trifluoro-butadiene-1,3.

13. The process that comprises chlorinating 1-bromo- 2-chloro 1,1,2trifluorobutene 3, recovering 1 bromo-2,3,4,4tetrachloro-1,l,Z-trifluorobutane as a product, de- 60bromodechlorinating said product to remove the bromine atom from thefirst carbon atom and one atom of chlorine from the fourth carbon atomto form 4-chloro-1,1,2- triflurobutadiene-1,3.

References Cited in the file of this patent UNITED STATES PATENTS2,647,110 Wiseman July 28, 1953 2,681,942 Ruh et a1 June 22, 19542,686,207 Crane et al Aug. 10, 1954 2,749,376 Tarrant et a1 June 5, 19562,750,431 Tarrant et a1 June 12, 1956 FOREIGN PATENTS 856,145 GermanyNov. 20, 1952 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent Noo 3,020,267 February 6, 1962 John '1, Barr It is herebycertified that error appears in the above numbered patent requiringcorrection and that the said Letters Patent should read as correctedbelow.

Column 4, line 71, for "-isobytryronitrile" read -isobutyronitrilecolumn 5, line 68, after "-1,3;' second occurrence, insert3-ch1orocolumn 8, line 59, for

"cholro" read ch loro column 9, line 7, for "choloro read chloro Signedand sealed this 29th day of May 1962.

fittest:

ERNEST w. SWIDER DAVID-L LADD Atteeting Officer Commissioner of Patents

1. A POLYMER SELECTED FROM THE GROUP CONSISTING OF POLYMERICCF2=CF-CCI=CH2, CF2=CF-CH=CHCI AND CF2=CF-CCI=CHCI.